Billionaire founders of Facebook Inc. (FB), Amazon.com Inc. (AMZN), Netflix Inc. (NFLX) and Alphabet Inc. (GOOG) saw $7.6 billion erased from their fortunes Wednesday after the Nasdaq 100 suffered its worst day in over three months.

The biggest loser was Facebook’s Mark Zuckerberg, who lost nearly $3 billion according to Bloomberg Billionaires Index. Amazon’s Jeff Bezos saw his net worth fall about $2.5 billion, below the $100 billion he surpassed on Black Friday and Cyber Monday enthusiasm. Sergey Brin and Larry Page of Alphabet, Google’s parent company, lost $1 billion each. Netflix’s Reed Hastings, who just this October joined Forbes 400 List of Richest Americans for the first time, saw his net worth drop $133 million over the day.

Behind the sell-off in shares of America’s tech giants is a larger move by investors to stocks they expect to benefit the most from President Trump’s proposed tax plan. FANG stocks, semiconductor picks and the Nasdaq Composite all tanked on Wednesday while the Financial Select Sector SPDR Fund spiked about 2%. (See also: Trump Tax Plan ‘As Good as It Gets’ for US Banks.)

Who Benefits Most From Tax Plan?

Technology stocks currently benefit from an 18.5% effective tax rate, the third-lowest among U.S. large caps, according to S&P Global data. As a result, investors see less of a major reward for America’s tech titans than other segments, such as banking, assuming that the current Republican tax legislation moves through the Congress.

This week, analysts at Morgan Stanley offered another blow to semiconductor plays, lowing their rating on shares of Western Digital Corp. (WDC), Samsung Electronics and Taiwan Semiconductor (TSM) from overweight to equal weight.

Facebook, Amazon, Netflix and Alphabet, which saw their shares drop 4%, 2.7%, 5.5% and 2.4%, respectively, on Wednesday, are all seeing a sligh rebounding as of Thursday afternoon. (See also: Credit Suisse Picks Its Tax-Reform Winners.)

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